Oil used as a lubricant in engines or as a prime mover in fluid drive units must be cooled to avoid overheating. Oil coolers used to maintain an acceptable oil temperature level have normally been of the tube and fin radiator type. The design of these units normally includes a flow path defined by tubing formed into a tortuous path having a multitude of fins pressed thereon in heat exchange relation. The oil, upon flowing through the tubing, is cooled as a result of heat exchange with the surrounding atmosphere. While these radiators provide effective heat exchange for oil or other fluids, they are expensive to produce and, at times, are difficult to repair when a leak develops therein.
Core-type oil coolers have also been used. Such an oil cooler is disclosed in U.S. Pat. No. 1,983,466 to J. E. Kline, issued Dec. 4, 1934. In the oil cooler disclosed in the Kline patent, an inner core is mounted concentrically within an outer cylindrical shell. A series of annular baffles are arranged between the core and the shell with a portion of each baffle being cut away to form a port. The ports of alternate baffles are arranged at diametrically opposed sides of the cooler such that oil is made to flow along upward and downward paths between the baffles as the fluid moves from an inlet pipe through the cooler to an exit pipe.
Although such oil coolers have provided an alternative to the fin-type radiator units, these coolers are also expensive and have been somewhat insufficient in the degree of heat exchange provided. Therefore, a need has arisen for a fluid cooler which is both economical to produce and is effective in providing a heat exchange relationship between the fluid and the surrounding atmosphere.